Spectrometer systems can be used to determine the concentration, e.g., relative amount, of one or more components contained in a mixture. For example, spectrometer systems can be used to determine the concentration of one or more gasses contained in a gaseous mixture. A cavity ring-down spectrometer system is one type of spectrometer system than can be used to determine the concentration of one or more gasses contained in a gaseous mixture.
A cavity ring-down spectrometer system can include a source laser, a cavity having at least two mirrors, and a ring-down detector. The laser can provide light into the cavity through one of the mirrors, and the light can reflect through the cavity and exit (e.g., leak out of) the cavity through one of the mirrors. When the light in the cavity is in resonance, the power and/or intensity of the light in the cavity can increase. The laser can then be turned off, and the rate at which the light exits the cavity (e.g., the rate at which the power and/or intensity of the light exiting the cavity decreases) can be measured by the ring-down detector and used to determine the concentration of one or more gasses contained in a gaseous mixture in the cavity.
The ring-down detector, however, can be saturated by light exiting the cavity before the laser is turned off (e.g., before the cavity passes into resonance). The saturation of the ring-down detector can decrease the range, precision, and/or accuracy of the ring-down detector's subsequent measurement of the rate at which light exits the cavity after the laser is turned off. Accordingly, the saturation of the ring-down detector can decrease the range, precision, and/or accuracy of gas concentrations determined by the cavity ring-down spectrometer system.